package com.huaiseng.xinglu.message;

import java.io.File;
import java.math.BigDecimal;

import android.content.Context;
import android.os.Environment;

/**
 * 计算缓存大小、清空缓存操作类
 *
 * @author Developer_x
 * @version
 * @date
 */
public class DataCacheManager {
	/**
	 * 检查当前项目文件缓存的大小
	 *
	 * @param context
	 * @return
	 * @throws Exception
	 */
	public static String getTotalCacheSize(Context context) throws Exception {
		long cacheSize = getFolderSize(context.getCacheDir());
		if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
			cacheSize += getFolderSize(context.getExternalCacheDir());
		}
		return getFormatSize(cacheSize);
	}

	/**
	 * 清空当前项目的缓存
	 *
	 * @param context
	 */
	public static void clearAllCache(Context context) {
		deleteDir(context.getCacheDir());
		if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
			deleteDir(context.getExternalCacheDir());
		}
	}

	/**
	 * 删除缓存文件夹
	 *
	 * @param dir
	 * @return
	 */
	private static boolean deleteDir(File dir) {
		if (dir != null && dir.isDirectory()) {
			String[] children = dir.list();
			for (int i = 0; i < children.length; i++) {
				boolean success = deleteDir(new File(dir, children[i]));
				if (!success) {
					return false;
				}
			}
		}
		return dir.delete();
	}

	/**
	 * 计算当前文件夹的大小
	 *
	 * @param file
	 * @return
	 */
	public static long getFolderSize(File file) {
		long size = 0;
		try {
			File[] fileList = file.listFiles();
			for (int i = 0; i < fileList.length; i++) {
				// 如果下面还有文件
				if (fileList[i].isDirectory())
					size = size + getFolderSize(fileList[i]);
				else
					size = size + fileList[i].length();
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
		return size;
	}

	/**
	 * 格式化单位
	 *
	 * @param size
	 * @return
	 */
	public static String getFormatSize(double size) {
		double kiloByte = size / 1024;
		if (kiloByte < 1) {
			return size + "";
		}
		double megaByte = kiloByte / 1024;
		if (megaByte < 1) {
			BigDecimal result1 = new BigDecimal(Double.toString(kiloByte));
			return result1.setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString() + "KB";
		}
		double gigaByte = megaByte / 1024;
		if (gigaByte < 1) {
			BigDecimal result2 = new BigDecimal(Double.toString(megaByte));
			return result2.setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString() + "MB";
		}
		double teraBytes = gigaByte / 1024;
		if (teraBytes < 1) {
			BigDecimal result3 = new BigDecimal(Double.toString(gigaByte));
			return result3.setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString() + "GB";
		}
		BigDecimal result4 = new BigDecimal(teraBytes);
		return result4.setScale(2, BigDecimal.ROUND_HALF_UP).toPlainString() + "TB";
	}
}
